This invention relates to a medical instrument arrangement, for example, a medical instrument for use in surgical operations carried out under sterile conditions. This instrument arrangement includes a carrier unit carrying an instrument unit, a drape covering the instrument unit at least partially and a suction unit for removing medium from the drape. This invention further relates to a method for operating such instrument arrangement.
In surgical operations various medical instruments are used. The parts of such instruments which are exposed to a field of operation have to be sterile. Generally, on an optical microscope this is achieved by a transparent, sterile drape placed around the optical setup of the instrument. In the region of the objective lens system of microscope, such drape has a window opening for allowing a good and clear view of the field of operation. However, due to its bulkiness, such drape may restrict the view on the field of operation both for the surgeon and the assistants. A bulky drape reduces the space between the field of operation and the medical instrument where various operating tools are manipulated and passed. Furthermore, a bulky drape may be a handicap for a surgeon or an assistant to work or pass below a carrier arm of the instrument which is protected by the drape. In addition, the handling and actuation of control buttons of the medical instrument which lie under the drape is uncomfortable and may lead to errors in manipulation if there is a bulky drape around the medical instrument.
In xe2x80x9cBNI QUARTERLYxe2x80x9d vol. 4 (2), 1988, it has been suggested to use suction for eliminating the disturbing bulkiness of such a drape placed around an operation microscope used in surgical operations. It is reported that such suction can be carried out by attaching a suction tube to the frame of the microscope-head while snugly closing the end of the drape at the horizontal arm of the microscope stand with a Penrose drain. With the drape deflated, it assumes the outline of the original microscope and stand. The deflated microscope drape increases the visual field of the operating nurse and assistant and allows them greater access to pass instruments underneath or around the microscope.
The object of the invention is to provide an instrument arrangement which can be equipped with a sterile drape while allowing for easy handling and to provide a method for operating such instrument in a way that negative effects of the drape on a surgical operation or procedure are minimized.
This object is achieved by an instrument arrangement having a carrier unit carrying an instrument unit and packing means provided on a portion of the carrier unit to which a drape can be fixed, while there is a suction unit for removing medium from the drape. Such packing can have the form of a collar, of a sleeve or the like. The packing can be provided with pass-throughs for suction tubes and allows for a more or less gastight closure of the drape to the microscope stand. If the drape is fixed to the collar by means of a VELCRO fastening, a tape or the like, such drape can be changed easily and rapidly for sterilization. The suction unit of the instrument may include a pump which is arranged in a stand or ceiling mount of the instrument in a way that pumping vibrations are not transmitted to the instrument unit. Alternatively, the suction unit may be designed to be connected to some external stationary pumping unit as in a standard operating room in general.
In a preferred embodiment there is a suction unit with an exit for medium removed from the drape, which is arranged at a clear and safe distance from the instrument unit. In this way, the air drawn out of the drape is guided and discharged far away from the field of operation and infections of a surgical wound can be avoided.
If the suction unit includes a pump with a turbine, vibrations related to suction which disturb the view of the surgeon through an operation microscope can be minimized.
Preferably the suction unit is at least partially integrated into the carrier unit and into the instrument unit. Such suction unit allows for a compact design of a medical instrument and for a medical instrument which can be transported easily.
In a preferred embodiment of the instrument arrangement, means to control a suction rate are provided. Such instrument allows for adapting a suction rate to an instantaneous leak rate.
Very effective suction of air from the drape can be achieved in that one or more openings for removing medium from the drape are provided in the suction unit.
In another preferred embodiment of the instrument arrangement, means are provided for preventing obstruction of the one or more openings of the suction unit by the drape. In this way, a very reliable medical instrument is provided.
Preferably, there are means for ventilating the drape. These means for ventilating the drape may include a valve or a pump, for example, a turbo engine or the like which not only removes fluid but can be reversed as well. Such instrument allows for easy and fast change of the drape between two surgical operations.
If there is a suction unit with a tube in the instrument arrangement which is at least partially bendable, the tube system has no negative impact on the maneuverability of a microscope stand. It is also possible to provide a pipe system having link joints for the suction unit. Such instrument arrangement has a very solid system for removing air from the drape.
A method for operating a corresponding instrument arrangement includes the steps of removing medium from a drape at least partially covering an instrument unit of the instrument by means of a suction unit at a first suction rate in a first operating state of the instrument and removing medium from a drape at least partially covering an instrument unit of the instrument by means of a suction unit at a second suction rate in a second operating state of the instrument, the first suction rate being greater than the second suction rate. Such method allows for a rapid preparation of the instrument for a surgical operation.
By ventilation, the drape around the instrument can be removed easily in order to replace it by a new, sterile one.